title: Characterization of ²⁴¹ Am and ¹³⁴Cs bioaccumulation in the king scallop Pecten maximus: investigation via three exposure pathways.
abstract: In order to understand the bioaccumulation of (241)Am and (134)Cs in scallops living in sediments, the uptake and depuration kinetics of these two elements were investigated in the king scallop Pecten maximus exposed via seawater, food, or sediment under laboratory conditions. Generally, (241)Am accumulation was higher and its retention was stronger than (134)Cs. This was especially obvious when considering whole animals exposed through seawater with whole-body concentration factors (CF(7d)) of 62 vs. 1, absorption efficiencies (A(0l)) of 78 vs. 45 for seawater and biological half-lives (T(b½l)) of 892 d vs. 22 d for (241)Am and (134)Cs, respectively. In contrast, following a single feeding with radiolabelled phytoplankton, the assimilation efficiency (AE) and T(b½l) of (134)Cs were higher than those of (241)Am (AE: 28% vs. 20%; T(b½l): 14 d vs. 9 d). Among scallop tissues, the shells always contained the higher proportion of the total body burden of (241)Am whatever the exposure pathway. In contrast, the whole soft parts presented the major fraction of whole-body burden of (134)Cs, which was generally associated with muscular tissues. Our results showed that the two radionuclides have contrasting behaviors in scallops, in relation to their physico-chemical properties.
authors.affiliation: International Atomic Energy Agency, Marine Environment Laboratories, 4, Quai Antoine Ier, MC-98000, Principality of Monaco, Monaco. metian@hawaii.edu
authors.forename: Marc
authors.initials: M
authors.lastname: Metian
authors.forename: Michel
authors.initials: M
authors.lastname: Warnau
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Teyssié
authors.forename: Paco
authors.initials: P
authors.lastname: Bustamante
mesh_terms: D000576:Americium / Q000493:pharmacokinetics / Q000633:toxicity*; D000818:Animals; D002588:Cesium Radioisotopes / Q000493:pharmacokinetics / Q000633:toxicity*; D020387:Food Chain; D005602:France; D019015:Geologic Sediments / Q000032:analysis; D006207:Half-Life; D007700:Kinetics; D049910:Pecten / Q000187:drug effects* / Q000378:metabolism; D012623:Seawater / Q000032:analysis; D014875:Water Pollutants, Radioactive / Q000493:pharmacokinetics*
chemical_list: D002588:Cesium Radioisotopes; D014875:Water Pollutants, Radioactive; D000576:Americium